| 主权项 |
1. A communication node comprising:
a plurality of antennas; a plurality of radio circuits configured to transmit and receive in compliance with IEEE 802.11 standard; and a baseband processor, wherein said plurality of radio circuits and antennas are located within a clear channel assessment (CCA) range of a number N neighboring nodes sharing a co-channel with the communication node, wherein the baseband processor is configured to set weights on the radio circuits such that spatial signatures are generated in both downlink and uplink transmissions, for allowing said communication node to access said co-channel, known by said communication node_to be currently used by at least one of the N neighboring nodes, by reducing a power level of signals transmitted by said antennas, as received by said N neighboring nodes, below a CCA range power level, wherein the nulling created by said nulling AP, are in both downlink and uplink toward to the nulled APs, wherein said communication node is a nulling Access point (AP) and the neighboring nodes are nulled APs, and wherein the APs communicate in compliance with the 802.11 standard, wherein the nulling created by said nulling AP, are in both downlink and uplink toward to the nulled APs, and wherein the nulling AP performs channel estimation of the nulled AP's preamble Legacy-Long Training Field (L-LTF) field, calculates Rx null weights and uses reciprocity to create the downlink Tx null. |
